预制裂纹岩石压剪试验的数值模拟分析
|
摘要
采用岩石破裂过程分析软件RFPA2D对预制裂隙大理岩试样的压剪试验进行数值模拟。数值分析表明,次生裂纹基本沿裂纹尖端萌生和扩展,所形成翼裂一般逐步趋向与荷载方向一致,这和试验结果是相吻合的。尽管某些数值分析结果和试验结果并不完全符合,但数值分析的模型和参数基本上有效地模拟了真实岩体介质的不均质性等力学特性。同时,采用该软件分析了加工小孔对裂尖应力状况的影响,加工小孔的存在对试验结果有一定影响,但并没有实质性影响。其影响主要在两方面一是使翼裂起裂角变大,扩展路径变曲折;二是使材料更易于在裂尖引发二次(剪切)裂纹。最后,对锯齿形裂纹模型进行了初步的数值模拟。
A numerical simulation of the experiment on rock with preexisted cracks under compression is presented by using a rock failure process analysis code,RFPA2D. It is shown that most of the wing cracks initiate from the tips of preexisted cracks and eventually align themselves with the load direction. This result is of good agreement with the previous experiment. Though some numerical results do not agree with the experimental data completely,the heterogeneity of real rock material is simulated effectively with the models and parameters. By analyzing the stress field near the tips of cracks,it is shown that there is no essential influence of processing small holes on the failure mechanism of rock,although the small holes make the initiation angles of wing cracks become large and facilitate the initiation of secondary shear cracks. Lastly,a preliminary numerical analysis is made on the zigzag cracks.
A numerical simulation of the experiment on rock with preexisted cracks under compression is presented by using a rock failure process analysis code,RFPA2D. It is shown that most of the wing cracks initiate from the tips of preexisted cracks and eventually align themselves with the load direction. This result is of good agreement with the previous experiment. Though some numerical results do not agree with the experimental data completely,the heterogeneity of real rock material is simulated effectively with the models and parameters. By analyzing the stress field near the tips of cracks,it is shown that there is no essential influence of processing small holes on the failure mechanism of rock,although the small holes make the initiation angles of wing cracks become large and facilitate the initiation of secondary shear cracks. Lastly,a preliminary numerical analysis is made on the zigzag cracks.
引文
1唐春安,赵文.岩石破裂全过程分析软件系统RFPA
2D[J].岩石力学与工程学报,1997,16(5):507～5082Tan gCA.Numeric alsimulati on ofro ckfailu rea ndassociat edseismicity[J].Int.J.RockMech.Min.Sci.,1997,34(2):249～262
3T angCA, KouSQ.C rackpropaga tio nandcoalesc en ceinbri ttlemater ialsu ndercompression[J].Engng.Fract.Mech.,1998,61(3/4):311～324
4陈忠辉,谭国焕,杨文柱.不同围压作用下岩石损伤破坏的数值模拟[J].岩土工程学报,2001,23(5):576～580
5唐春安,黄明利,张国民等.岩石介质中多裂纹扩展相互作用及其贯通机制的数值模拟[J].地震,2001,21(2):54～58
6傅宇方,梁正召,唐春安.岩石介质细观非均匀性对宏观破裂过程的影响[J].岩土工程学报,2000,22(6):706～710
7黄明利,唐春安,梁正召.岩石裂纹相互作用的应力场分析[J].东北大学学报(自然科学版),2001,22(4):447～449
8黄明利,唐春安,朱万成.岩石破裂过程的数值模拟研究[J].岩石力学与工程学报,2000,19(4):468～471
9李银平.岩石类材料损伤断裂机理分析[博士学位论文][D].武汉:华中科技大学,2003
10李银平,王元汉.压荷载下类岩石材料中的锯齿形裂纹分析[J].固体力学学报,2003,24(4):456～462
2D[J].岩石力学与工程学报,1997,16(5):507～5082Tan gCA.Numeric alsimulati on ofro ckfailu rea ndassociat edseismicity[J].Int.J.RockMech.Min.Sci.,1997,34(2):249～262
3T angCA, KouSQ.C rackpropaga tio nandcoalesc en ceinbri ttlemater ialsu ndercompression[J].Engng.Fract.Mech.,1998,61(3/4):311～324
4陈忠辉,谭国焕,杨文柱.不同围压作用下岩石损伤破坏的数值模拟[J].岩土工程学报,2001,23(5):576～580
5唐春安,黄明利,张国民等.岩石介质中多裂纹扩展相互作用及其贯通机制的数值模拟[J].地震,2001,21(2):54～58
6傅宇方,梁正召,唐春安.岩石介质细观非均匀性对宏观破裂过程的影响[J].岩土工程学报,2000,22(6):706～710
7黄明利,唐春安,梁正召.岩石裂纹相互作用的应力场分析[J].东北大学学报(自然科学版),2001,22(4):447～449
8黄明利,唐春安,朱万成.岩石破裂过程的数值模拟研究[J].岩石力学与工程学报,2000,19(4):468～471
9李银平.岩石类材料损伤断裂机理分析[博士学位论文][D].武汉:华中科技大学,2003
10李银平,王元汉.压荷载下类岩石材料中的锯齿形裂纹分析[J].固体力学学报,2003,24(4):456～462
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心